SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62baae7c6f82fb309022574efcf181dda359124ae4e374b1fd8644801c46fe66' 
  AND token = 'dIDWzCpX9vS7cZfFh3pGpR+mIAbCdHDoRhdBn2CNwiA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}